Valve and pump devices for expelling fluid from vessels

ABSTRACT

A pump apparatus for use with a vessel to selectively expel fluid from the vessel, the apparatus comprising a housing with an internal chamber having first and second portions, the first portion includes an inlet port and an outlet port that communicates with the outside of the vessel; a conduit connected to the inlet port and in fluid communication with the inside of the vessel; a stopper mounted within the first portion and being movable to seal and unseal the outlet port for regulating the expulsion of fluid from the chamber; a reciprocating member moveably mounted within the second portion and being dimensioned for a close fit therein, and further being connected to the stopper and having a larger exposed surface area than the stopper, such that the reciprocating member moves in a first direction in response to an increase in fluid pressure in the first portion causing the stopper to unseal the outlet port, and moves in an opposite second direction when the fluid pressure in the first portion returns to that of the resting state of the apparatus, thereby enabling the stopper to seal the outlet port; and a means for selectively increasing the fluid pressure in the first portion of the chamber to actuate the reciprocating member.

BACKGROUND OF THE INVENTION

The present invention relates generally to devices for pumping fluid,and more specifically, to devices for expelling fluid from a vessel orother fluid containers, and even more specifically to pump devices foruse with firefighting containers transportable by helicopter forcarrying fire retardants, foams, gels or water wherein the pump devicesselectively expel said fluid material from the firefighting container.

It is often desirable to expel quantities of fluid from a vessel orother fluid container having fluid therein in order to control theamount of fluid remaining in the vessel. For example, large fires areoften fought using aircraft to drop fire retardants, foams, gels orwater, either directly on the fire or at nearby locations to create afire break. A very effective approach to this kind of fire fighting usesa large vessel or bucket suspended from a helicopter. Helicopters aregenerally used for sustained fire fighting operations because they aremore versatile than fixed wing aircraft. Since a helicopter does notrequire a landing strip, the bucket can be filled, without landing thehelicopter, at a nearby body of water or at a temporary staging area setup to maintain a supply of fire retardant fluid close to the fire bysimply dunking the bucket into the source. This reduces the amount oftime required between drops, which likewise reduces the time required toextinguish the fire.

The lifting capacity of any given helicopter, hence the amount of fluidthe helicopter is able to carry in a bucket at any given time, varieswith the amount of fuel in the helicopter and with the weight of othercargo on board. Accordingly, after having filled the bucket from asource, it would be desirable for the pilot to be able to expel fluidfrom the bucket in order to reduce the weight of the load to a desiredlevel before lifting off with the loaded bucket, thereby being able tomaximize the amount of fluid carried based on the lifting capacity ofthe helicopter at that particular moment.

SUMMARY OF THE INVENTION

The present invention provides valve and pump devices that are compactso that they are useable with a vessel, tank or other fluid container,such as inside a firefighting bucket, that are efficient, and that areremotely controllable, such as from the cockpit of an aircraft or thelike.

Accordingly, in some embodiments of the present invention there isprovided a pump device for use with a vessel for selectively expellingfluid from the vessel comprising a housing defining an internal chamberhaving first and second portions, the second portion being larger incross-section than the first portion and being in fluid communicationwith fluid in the vessel when the apparatus is operably mounted with thevessel, the first portion of the housing further including a fluid inletport and a fluid outlet port, wherein the chamber is in fluidcommunication with the fluid in the vessel via the inlet port; connectormeans cooperating with the housing for mounting the apparatus on thevessel in a manner that the outlet port communicates with the outside ofthe vessel through the wall of the vessel, wherein the chamber is influid communication with the atmosphere via the outlet port; a stoppermounted within the first portion of the housing and being movable toseal and unseal the outlet port to regulate the expulsion of fluid fromthe chamber, the stopper being biased towards sealing the outlet portwhen apparatus is in a resting state; a piston reciprocating within thesecond portion and being connected to the stopper, the piston furtherhaving a larger exposed surface area than the stopper, wherein thepiston moves in a direction away from the outlet port in response to anincrease in fluid pressure in the first portion causing the stopper tounseal the outlet port, and moves in the opposite direction in responseto the biasing force acting on the stopper when the fluid pressure inthe first portion returns to that of the resting state of the apparatus,thereby enabling the stopper seal the outlet port; and a means forselectively increasing the fluid pressure in the first portion of thechamber with fluid from the vessel via the inlet port. The piston andstopper may be moveable in a linear path along the same axis. In someembodiments, the piston and stopper are moveable along the axis of thechamber. The apparatus may include a rod mounted for reciprocatingmovement along the axis of the chamber, and having one end connected tothe stopper, and an opposite end connected to the piston. The piston maybe moveable in relation to the rod, and the apparatus further includes aretainer at the opposite end and a coil spring mounted on the rodbetween the retainer and the piston for biasing the piston away from theretainer.

In some embodiments, the first portion of the chamber is cylindrical,and the first and second portions are coaxial. The stopper may bedimensioned to fit closely within the first portion of the chamber.

In some embodiments, the inlet port and the outlet port aresubstantially at a right angle to each other. The stopper may be biasedby a coil spring having one end connected to the housing and the otherend abutting the stopper.

In some embodiments, the means for selectively increasing the fluidpressure in the first portion comprises a duct connected to the inletport and communicating with the fluid in the vessel, an impeller mountedfor rotation within the duct, a submersible motor electrically coupledto a power source and connected to the duct for driving the impeller,and a remote switch connected to the motor for activating anddeactivating the motor. Stator vanes may be included within the duct andlocated downstream from the impeller.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention and to show moreclearly how it may be carried into effect, reference will now be made byway of example to the accompanying drawings in which:

FIG. 1 is a medial section view of an embodiment of the presentinvention shown mounted in the vertical wall of a vessel or other fluidcontainer;

FIG. 2 is a medial section view of the device in FIG. 1 shown with theoutlet port in a sealed position;

FIG. 3 is a medial section view of the device in FIG. 1 shown with theoutlet port in an open position;

FIG. 4 is a front elevation view of the device in FIG. 1;

FIG. 5 is a rear elevation view of the device in FIG. 1;

FIG. 6 medial section view of another embodiment of the presentinvention shown with the outlet port in a sealed position; and

FIG. 7 is a medial section view of the device in FIG. 6 shown with theoutlet port in an open position.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the exemplary embodimentsillustrated in the drawings, and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of the invention is thereby intended. Any alterations andfurther modifications of the inventive features illustrated herein, andany additional applications of the principles of the invention asillustrated herein, which would occur to one skilled in the relevant artand having possession of this disclosure, are to be considered withinthe scope of the invention. Therefore, specific details disclosed hereinare not to be interpreted as limiting, but rather as a basis for theclaims and as a representative basis for teaching one skilled in the artto employ the present invention.

Referring to FIG. 1, an embodiment of the present invention is generallyindicated at 10 and is shown mounted inside a vertical wall 12 of avessel or other fluid container, adjacent the bottom 13 of the vessel.In particular, device 10 is well suited to being mounted inside a watertank or bucket of the kinds typically transported by helicopter for usein fighting fires, wherein device 10 is advantageously employed toremotely reduce the weight of the tank or bucket by expelling watertherefrom to achieve a desired weight. However, the device may be usedin a multitude of other applications than those discussed herein.

Referring to FIGS. 1-5, device 10 has a valve housing 20 comprising oftwo longitudinally aligned tubular portions 22 and 24, and defining aninternal chamber having two longitudinally aligned coaxial cylinderportions or sub-chambers 26 and 28 of differing cross-sectionaldimensions. Sub-chamber 28 is larger in cross-section than sub-chamber26. At the juncture of tubular portions 22 and 24, there is definedcircumferential internal shoulder 30 in the housing wall. At end 32 ofthe housing adjacent sub-chamber 26 is a tubular outlet port 34 that iscentered on the axis 36 of the chamber, and which communicates withsub-chamber 26. The diameter of the outlet port 34 is less than thediameter of tubular portion 22, and the juncture of the two defines ashoulder 38 having a flat outer surface 40 and a tapered inner surface42 that provides a seating and sealing surface. Outlet port 34 includesthreads 44 adjacent said shoulder and a gland nut 46 cooperating withthe threads for mounting the device within a bore of a vessel wall 12(as shown in FIG. 1) such that the portion of the wall adjacent the boreis sandwiched between nut 46 and flat surface 40. While the device isdescribed herein as being mounted inside a vessel, it is to beunderstood that the device may be used externally of the vessel providedthat a conduit communicates fluid from the vessel to the chamber of thedevice for the purpose of emptying the vessel.

The housing 20 along the length of tubular portion 22 is provided withan inlet port 50 that communicates with sub-chamber 26, and which issubstantially aligned at right angle to the outlet port 34. To the inletport 50 is connected a means for selectively increasing the fluidpressure in sub-chamber 26, such as for example, an axial flow pump 54that draws fluid from the vessel and delivers it under pressure to saidsub-chamber.

Axial flow pump 54 has a tubular duct 56 that is connected to the inletport 50 at one end and to a submersible electric motor 58 at the otherend. Hence the duct communicates with sub-chamber 26. Within the duct 56is provided an impeller 60 that is driven by the motor, and stator vanes62 located downstream from the impeller. Preferably, each stator vane isangled from between 30 and 60 degrees to the axis 64 of the duct fordisturbing fluid flow there through. Inlet openings 66 are locatedupstream from the impeller around the circumference of the duct 56 andenable fluid from the vessel to flow into the duct. A source of power isprovided to the motor by a waterproof electrical conduit 68 that isconnected to a switch (not shown) to enable an operator to selectivelyenergize the pump, hence pressurize and unpressurize sub-chamber 26.

The internal surface of the valve housing wall adjacent shoulder 30 isfurther provided with a circumferential groove 70 into which is fixedlyconnected a circular disk 72 having a central bore 74 that is centeredon the axis 36 of the chamber, and a plurality of fluid ports 76 thatpermit fluid flow between sub-chambers 26 and 28. The surface of thedisk and the surface of shoulder within sub-chamber 28 are coplanar, andprovide a seat for a piston 82 that reciprocates within sub-chamber 28.

Referring to FIGS. 2 and 3, a piston rod 84 is mounted within centralbore 74 of disk 72 for reciprocating movement along the axis 36 of thechamber. One end of the rod is connected to a circular sealing stopper90 having a tapered outer surface 92 that is complimentary to theseating and sealing surface 42 and enables the stopper 90 to seattherein to provide a fluid tight seal of the outlet port 34. The stopper90 is biased towards the outlet port by a biasing means such as coilspring 94 that surrounds the piston rod 84 and abuts the stopper 90 anddisk 72. The other end of the piston rod is connected to the piston.Accordingly, the piston, piston rod, stopper and spring comprise a valveassembly. Surfaces 96 and 98 of the stopper and the piston respectively,are each exposed to fluid pressure within the sub-chamber 26 and arereferred to herein as exposed surfaces. The exposed surface area of thepiston is larger than the exposed surface area of the stopper. The valveassembly moves on the principal of unequal forces that is provided byfluid pressure in sub-chamber 26 induced by the pump 54 and acting ontwo ‘pistons’, in effect, being the stopper 90 and piston 82. Theunequal forces are achieved by using unequal, but linearly connected,piston areas within the valve, in effect, being the exposed surfaceareas 96 and 98. The stopper acts as the smaller of the two pistons, aswell as a means of sealing the outlet port within the device. The outletport can be closed or opened based on the energized state of the pump,which is controlled by a remote switch. When the pump is energized, theunequal forces impart a motion on the valve assembly by forcing thepiston 82, having the larger exposed surface area, to move in adirection away from the outlet port, thereby causing the stopper 90 tomove in that direction as well. The unequal forces overcome allresisting forces that act to keep the stopper in the closed position,such as for example suction, stiction, friction, and the biasing forceof spring 94, causing the stopper to expose the outlet port and thecontained liquid to be released there through. With the outlet portopen, the pump forces the contained liquid through the outlet port.De-energizing the pump removes the unequal forces on the pistons, andthe biasing force of spring 94 acting on the stopper repositions thestopper (and valve assembly) to a sealing state in which the stopperseals the outlet port.

The dimensions of the exposed surface areas of the stopper and pistonare dependant upon the resisting forces that must be overcome in orderto un-stop the outlet port. For example, variables such as the type offluid, the depth of the fluid in the vessel, the pressure generated bythe pump, the spring constant of spring 94, and the angle and size ofthe stators may affect the relative exposed surface areas that must beused to impart sufficient hydraulic force onto the piston 82 to move thevalve assembly.

An embodiment of the present invention used to expel water from an opentank having a maximum water depth of 8.5 feet comprises spring 94 havinga spring constant (k) of 0.5 lb/inch; a 28V DC pump motor drawing up to15 Amps and driving a three bladed impeller measuring three and aquarter inches in diameter; the ratio of the exposed surface areas ofthe piston to the stopper being 1.5:1 or more, and preferably in therange of 1.5:1 to 4:1 (the upper end being dictated primarily bypracticality due to size differences in the housing). However, it isshould be understood that other combinations of parameters from thosedescribed above may be used and are within the scope of the presentinvention.

Referring to FIGS. 6 and 7, another embodiment of the present inventionis indicated generally at 110. Device 110 is the same as device 10 inall aspects except in the valve assembly, and elements common to bothwill are referenced by the same numerals as in the description of device10.

In device 110, the piston 82 includes a central bore 114 that alignswith, and is the same size as bore 74 of disk 72. The second end of thepiston rod 84 is not directly connected to the piston, but rather itpasses through the central bore 114 and it includes a terminal retainerdisk 116 that provides an abutment for an end of a second coil spring118 located between the retainer disk and the piston 82, thereby biasingthe piston away from the terminal disk.

When system is off, the stopper 90 seals the outlet port 34 with the aidof the liquid head pressure and the biasing force of spring 94. When thesystem is turned on, the pump 54 is energized, pressurizing thesub-chamber 26, creating a hydraulic force on the exposed surface 98 ofthe piston, which is larger than the exposed surface 96 of the stopper90. Initially, the movement of the piston is resisted by spring 114until a point at which the hydraulic force on the piston suddenlyovercomes the resisting force of said spring. Once this occurs, theresulting action is a sudden lateral “jerking” or hammer action of thepiston as it builds inertia traveling to the end of its “free-play” andstrikes the retainer disk 116, which action is transmitted to the valveassembly causing it to simultaneously move the stopper laterally to openthe outlet port 34, thereby allowing the liquid to be pumped out of thevessel. The hammer action enables the use of a smaller piston/cylindercombination relative to the stopper than would otherwise be required inan embodiment without the hammer action (such as in device 10), in whichcase the hammer action is necessary to overcome suction and othersealing forces acting on the stopper 90. When system is switched off,the pump pressures stops, and the diaphragm returns to its originalsealing role.

An embodiment used to expel water from an open tank having a maximumwater depth of 8.5 feet comprises spring 94 and 116 having a springconstant (k) of 0.5 lb/inch; a 28V DC pump motor drawing up to 15 Ampsand driving a three bladed impeller measuring three and a quarter inchesin diameter; the ratio of the exposed surface areas of the piston to thestopper being 1.1:1 or more, and preferably in the range of 1.1:1 to 4:1(the upper end being dictated primarily by practicality due to sizedifferences in the housing). However, it is should be understood thatother combinations of parameters from those described above may be usedand are within the scope of the present invention.

It is to be noted that alternate means for selectively increasing thefluid pressure in sub-chamber 26 can be used, such as for example, afluid pump communicating with sub-chamber 26 through a third port (notillustrated) independent of inlet port 50 or outlet port 34, and fluidsother than the fluid to be emptied from the vessel may be used toincrease the fluid pressure in sub-chamber 26 and motivate the piston82. In such embodiments, axial flow pump 54 may be replaced by a conduitconnected to the inlet port 50 and which communicates with the inside ofthe vessel for the purpose of emptying the vessel, and the motive forcefor expelling the fluid once the stopper unseals the outlet port wouldbe provided by the head pressure of the fluid in the vessel.

While the above description and illustrations constitute preferred oralternate embodiments of the present invention, it will be appreciatedthat numerous variations may be made without departing from the scope ofthe invention, which is defined in the appended claims.

1. A valve apparatus for use with a vessel for selectively enabling theexpulsion of fluid from the vessel, the apparatus comprising: a housingdefining an internal chamber having first and second portions, whereinthe first portion of the housing includes a fluid inlet port that is influid communication with the inside of the vessel when the apparatus isoperably connected to the vessel and a fluid outlet port thatcommunicates with the outside of the vessel; a stopper mounted withinthe first portion of the housing and being movable to seal and unsealthe outlet port for regulating the expulsion of fluid from the chamber;a reciprocating member moveably mounted within the second portion andbeing dimensioned for a close fit therein, and further being connectedto the stopper and having a larger exposed surface area than thestopper, such that the reciprocating member moves in a first directionin response to an increase in fluid pressure in the first portioncausing the stopper to unseal the outlet port, and moves in an oppositesecond direction when the fluid pressure in the first portion returns tothat of the resting state of the apparatus, thereby enabling the stopperto seal the outlet port; and a means for selectively increasing thefluid pressure in the first portion of the chamber to actuate thereciprocating member.
 2. The apparatus of claim 1 wherein thereciprocating member and stopper are moveable in a linear path along thesame axis.
 3. The apparatus of claim 2 wherein the stopper is biasedtowards sealing the outlet port when the apparatus is in a restingstate.
 4. The apparatus of claim 3 wherein the means for increasingfluid pressure in the first portion communicates with the inlet port. 5.The apparatus of claim 4 wherein the reciprocating member and stopperare moveable along the axis of the chamber.
 6. The apparatus of claim 5further including a rod mounted for reciprocating movement along theaxis of the chamber, and having one end connected to the stopper and anopposite end connected to the reciprocating member.
 7. The apparatus ofclaim 6 wherein the reciprocating member is moveable in relation to therod, and the apparatus further includes a retainer at the opposite endand a biasing means mounted on the rod between the retainer and thereciprocating member for biasing the reciprocating member away from theretainer.
 8. The apparatus of any one of claims 6 and 7 wherein thesecond portion is cylindrical and the reciprocating member is a pistonwithin the second portion.
 9. The apparatus of claim 8 wherein the firstportion of the chamber is cylindrical, and the first and second portionsare coaxial.
 10. The apparatus of claim 9 wherein the stopper isdimensioned to fit closely within the first portion of the chamber. 11.The apparatus of claim 10 wherein the inlet port and the outlet port aresubstantially at a right angle to each other.
 12. The apparatus of claim11 wherein the stopper is biased by a coil spring having one endconnected to the housing and the other end abutting the stopper.
 13. Theapparatus of claim 12 wherein the ratio of the exposed surface area ofthe piston to the exposed surface area of the stopper is at least 1.5:1.14. A pump apparatus for use with a vessel to selectively expel fluidfrom the vessel, the apparatus comprising: a housing defining aninternal chamber having first and second portions, wherein the firstportion of the housing includes a fluid inlet port and a fluid outletport that communicates with the outside of the vessel; a conduitconnected to the inlet port and in fluid communication with the insideof the vessel; a stopper mounted within the first portion of the housingand being movable to seal and unseal the outlet port for regulating theexpulsion of fluid from the chamber; a reciprocating member moveablymounted within the second portion and being dimensioned for a close fittherein, and further being connected to the stopper and having a largerexposed surface area than the stopper, such that the reciprocatingmember moves in a first direction in response to an increase in fluidpressure in the first portion causing the stopper to unseal the outletport, and moves in an opposite second direction when the fluid pressurein the first portion returns to that of the resting state of theapparatus, thereby enabling the stopper to seal the outlet port; and ameans for selectively increasing the fluid pressure in the first portionof the chamber to actuate the reciprocating member.
 15. The apparatus ofclaim 14 wherein the means for increasing fluid pressure in the firstportion comprises an impeller mounted for rotation within the conduit, amotor electrically coupled to a power source and connected to theimpeller for rotating the impeller, and a remote switch connected to themotor for activating and deactivating the motor.
 16. The apparatus ofclaim 15 wherein the reciprocating member and stopper are moveable in alinear path along the same axis.
 17. The apparatus of claim 16 whereinthe stopper is biased towards sealing the outlet port when the apparatusis in a resting state.
 18. The apparatus of claim 17 wherein thereciprocating member and stopper are moveable along the axis of thechamber.
 19. The apparatus of claim 18 further including a rod mountedfor reciprocating movement along the axis of the chamber, and having oneend connected to the stopper and an opposite end connected to thereciprocating member.
 20. The apparatus of claim 19 wherein thereciprocating member is moveable in relation to the rod, and theapparatus further includes a retainer at the opposite end and a biasingmeans mounted on the rod between the retainer and the reciprocatingmember for biasing the reciprocating member away from the retainer. 21.The apparatus of any one of claims 19 and 20 wherein the second portionis cylindrical and the reciprocating member is a piston within thesecond portion.
 22. The apparatus of claim 21 wherein the first portionof the chamber is cylindrical, and the first and second portions arecoaxial.
 23. The apparatus of claim 22 wherein the stopper isdimensioned to fit closely within the first portion of the chamber. 24.The apparatus of claim 23 wherein the inlet port and the outlet port aresubstantially at a right angle to each other.
 25. The apparatus of claim24 wherein the stopper is biased by a coil spring having one endconnected to the housing and the other end abutting the stopper.
 26. Theapparatus of claim 25 wherein the ratio of the exposed surface area ofthe piston to the exposed surface area of the stopper is at least 1.5:1.27. A pump apparatus for mounting in transportable firefightingcontainers for selectively expelling fluid from such container, theapparatus comprising: a housing defining an internal chamber havingfirst and second portions, the second portion being larger incross-section than the first portion and being in fluid communicationwith fluid in the container when the apparatus is mounted in thecontainer, the first portion of the housing further including a fluidinlet port and a fluid outlet port, wherein the chamber is in fluidcommunication with the fluid in the container via the inlet port;connector means cooperating with the housing for mounting the apparatusin the container in a manner that the outlet port communicates with theoutside of the container through the wall of the container, wherein thechamber is in fluid communication with the atmosphere via the outletport; a stopper mounted within the first portion of the housing andbeing movable to seal and unseal the outlet port to regulate theexpulsion of fluid from the chamber; a reciprocating member moveablymounted within the second portion and being dimensioned for a close fittherein, and further being connected to the stopper and having a largerexposed surface area than the stopper, such that the reciprocatingmember moves in a first direction in response to an increase in fluidpressure in the first portion causing the stopper to unseal the outletport, and moves in an opposite second direction when the fluid pressurein the first portion returns to that of the resting state of theapparatus, thereby enabling the stopper to seal the outlet port; a ductconnected to the inlet port and communicating with the fluid in thecontainer; and a means for selectively increasing the fluid pressure inthe first portion of the chamber to actuate the reciprocating membercomprising an impeller mounted for rotation within the duct, asubmersible motor electrically coupled to a power source and connectedto the impeller for driving the impeller, and a remote switch connectedto the motor for activating and deactivating the motor.
 28. Theapparatus of claim 27 wherein the reciprocating member and stopper aremoveable in a linear path along the same axis.
 29. The apparatus ofclaim 28 wherein the stopper is biased towards sealing the outlet portwhen the apparatus is in a resting state.
 30. The apparatus of claim 29wherein the reciprocating member and stopper are moveable along the axisof the chamber.
 31. The apparatus of claim 30 further including a rodmounted for reciprocating movement along the axis of the chamber, andhaving one end connected to the stopper and an opposite end connected tothe reciprocating member.
 32. The apparatus of claim 31 wherein thereciprocating member is moveable in relation to the rod, and theapparatus further includes a retainer at the opposite end and a biasingmeans mounted on the rod between the retainer and the reciprocatingmember for biasing the reciprocating member away from the retainer. 33.The apparatus of any one of claims 31 and 32 wherein the second portionis cylindrical and the reciprocating member is a piston within thesecond portion.
 34. The apparatus of claim 33 wherein the first portionof the chamber is cylindrical, and the first and second portions arecoaxial.
 35. The apparatus of claim 34 wherein the stopper isdimensioned to fit closely within the first portion of the chamber. 36.The apparatus of claim 35 wherein the inlet port and the outlet port aresubstantially at a right angle to each other.
 37. The apparatus of claim36 wherein the stopper is biased by a coil spring having one endconnected to the housing and the other end abutting the stopper.